GREENWICH -- Just hours after investigators on Thursday announced new revelations about last week's robbery of a Greenwich Avenue bank, police said the same bank robber may have struck in town again.

At 4:25 p.m. Thursday, a man entered the Chase Bank at 137 West Putnam Ave. and handed the teller a note explaining he was armed and demanding cash, before escaping with several thousand dollars in hand, police said.

The robber's methods were nearly identical to those used in the Aug. 28 robbery of the People's United Bank at 410 Greenwich Ave. The subsequent police response then led to a shutdown of Metro-North Railroad's New Haven Line as officers searched trains.

Coupled with surveillance footage from the Chase bank showing the robber as a heavy-set Hispanic man, police say the similarities may be more than just coincidence.

"We're operating on the assumption that this is the same suspect," Lt. Kraig Gray said at the scene Thursday, reaffirming that belief later in the evening.

No one was hurt in the incident, and though a weapon was intimated, none was ever shown just as with the previous robbery.

The incident occurred only three hours after Greenwich police held a press conference detailing connections between the People's United robbery and similar holdup at a bank 50 miles away in Linden, N.J.

On Aug. 20, a man, described as being in his 20s, about 5 feet, 8 inches tall, with a medium build and a Spanish accent fled a Wells Fargo bank branch in Linden with an undetermined amount of cash after showing a teller a threatening note.

Following an email tip pointing out the visual similarities between the photos of the suspects for each case, New Jersey investigators reached out to Greenwich officers, Linden police said. Detectives from both municipalities are now working to locate the man, whose whereabouts remain unknown following Thursday's robbery.

As of Thursday evening, a sign on the door of the Chase Bank direct customers to two of its other locations on West Putnam Avenue.

Anyone with information about any robbery is asked to contact Greenwich detectives at 203-622-3620, Linden detectives at 908-474-8 537, or their local FBI office.

"Our belief is that he is probably in the tri-state, New York area and we want to make sure we branched out our coverage of this a little bit further than just the local Greenwich area," Gray said at Thursday's press conference.

Initially, police had been following a lead based on the observations of an off-duty officer who was driving near the Greenwich Avenue robbery. Investigators said the officer saw a man matching the robber's description -- short, heavyset, and wearing a tie and fedora-style hat -- entering a small silver-colored sedan with New York license plates ending in ANX or some combination of those letters.

"The entire outfit really sparked [the off-duty officer's] interest," said Gray. "At the time he didn't realize that was actually a bank robbery suspect because he was off duty in his private car, but once he realized what was going on, the match of similarities, he had a strong sense of recall of that moment."

The bank robber Thursday, however, was seen leaving in a dingy, dark-colored four-door sedan that may have had Connecticut plates.

Security footage from Thursday showed the robber wearing a black, flat-brimmed hat, a thermal shirt, and dark pants, similar to the clothes worn during the Linden robbery. Though witnesses from the Greenwich Avenue case said the robber spoke to the teller in Spanish, police said English was spoken to the Chase Bank teller, albeit with a strong Spanish accent, in line with Linden police reports.